The signs and symptoms of IdiopathicThe term idiopathic is used when there is no detectable reason for something. Intracranial Hypertension (IIH) can range from mild to severe. If left untreated, these findings can turn into permanent and debilitating complications.
The diagnosis of IIH is defined by the modified Dandy criteriaCriteria used for diagnosing patients with IIH.. The most reported symptoms of those diagnosed with IIH are: headaches, dizziness, nausea, vision loss, double vision₁ and pulsatile tinnitusA whooshing or throbbing noise heard in one or both ears that can range from annoying to debilitating. Highly associated with venous sinus stenosis..₂ The clinical signs associated with IIH are: elevated opening pressure with a lumbar punctureA procedure where a needle is placed in the lower part of the spine (the lumbar spine) to access cerebrospinal fluid., specific MRI findings, sixth nerve palsy, papilledemaSwelling of the optic nerve that carries visual signals from the eye to the brain., and radicular pain.₃
Here is a review of the most common signs and symptoms of IIH.
Headache
The most reported symptom associated with IIH is a headache. When pressure in the brain is increased, shifting of these anatomical structures will cause head pain. It can present in any form, can wax and wane, can be described as a tension-type or migraine-type, and can worsen with coughing or straining. A headache is experienced in 68-98% of patients with IIH.₁
A build up of pressure in the cranium will decrease the amount of space in the brain, compressing the eye and its neurovascular structures. With IIH, vision is usually first to be compromised with increased intracranial pressure causing a wide range of visual changes:
- Transient obscurations are when a person sees black spots, shadows or dark patches in one or both eyes that can occur over seconds or minutes. These visual disturbances are reported in 52-72% of patients with IIH.₁
- Blurry vision or double vision. This can occur slowly over a course of weeks or months.
- Visual field deficits can go unnoticed and are usually only appreciated during a comprehensive eye exam. Your visual field is the objects seen around the area of your central focus area.
- Vision Loss can occur over hours, days, or weeks. If vision loss occurs rapidly, fulminant IIH is considered. This finding requires emergency medical attention to prevent permanent total vision loss.
- Papilledema is a finding seen on fundoscopic examination of the eye. Papilledema occurs when there is increased pressure in the brain causing swelling to the optic disc and nerve. The optic nerve is what carries visual signals from the eye to the brain. Unfortunately, if this swelling is left untreated, it can lead to blindness.
Pulsatile Tinnitus
Is defined by the sensation of ringing, swooshing or pulsation in the ears and is reported in up to 60% of patients with IIH.₁ Also known as synchronous pulsatile tinnitus, the frequency and strength of these symptoms can be mild or debilitating, requiring high-dose prescription medications. Pulsatile tinnitus is commonly associated with venous sinus stenosis. Recent data has shown venous sinus stenting to effectively resolve pulsatile tinnitus if it is due to to narrowing of the dural venous sinuses.₄
Radicular pain
It is hypothesized that radicular pain is the effect of increased cerebrospinal fluidFluid that is made by specialized cells in the ventricles of the brain. pressure, compressing nerves in the arms and legs causing the sensation of pins and needles.
Sixth Nerve Palsy
This is the weakening of the lateral rectus muscle of the eye (innervated by the sixth cranial nerve) and can lead to double vision. Also known as abducens nerve palsy, it is a disorder that affects the ability to turn your eye away from your nose. With weakness of the lateral rectus muscle, your eye remains crossed inwards towards your nose.
There are also a constellation of symptoms not listed above that affects one with IIH such as fatigue, migraines, neck and shoulder pain, brain fog and much more. As IIH continues to be better understood through research, it will lead us to better diagnostic tools and treatment options. If you would like to learn more about the treatment for IIH, click here.